Pol-E: Large-obstacle Overcoming based on Energy Conversion Method Using an Elastic Link

Abstract

Jumping robots are being developed using a variety of methods, such as springs, compressed air, and elastic strips. We present a new robotic platform called Pol-E, which can jump using an elastic link based on the principle of pole vaulting and energy conservation theory. Wheeled locomotion is used to build up energy without additional actuators for jumping. Kinetic energy generated by moving on the ground is converted into elastic and potential energy by colliding with an obstacle through the elastic link. We modeled the dynamics as run-up, stance, and flight phases to predict the influences of design variables for the robot through a sensitivity analysis. The sensitivity analysis examined the initial velocity, stiffness of the elastic link, and the initial angle between the elastic link and the ground. Based on the results, we selected the best values for overcoming an obstacle. The prototype successfully jumped over an obstacle with a height of 0.18m, about 3 times the robot size. We expect the proposed robot platform to be applied to inspection, environmental monitoring, and search and rescue.